How to read the log files

Debugging a non-working setup can seem like a daunting task at first. Where should you begin? Luckily, OpenVPN provides excellent logging and debugging facilities. However, with increased logging verbosity, it also becomes increasingly difficult to read these log files. The default log level of OpenVPN is 1, but it is recommended that you set the verbosity to 3. This often gives the administrator enough information to detect setup issues, while keeping the performance penalty to a minimum.

Setting the verbosity to 5 or higher is recommended only for debugging purposes, as it will severely affect performance.

Every example in this book so far has included the setting verb 3. First, we will go through both client and server log files for a working setup with this verbosity. It is important to understand, and possibly even store, the log files of a working connection. When trying to find a bug in a non-working setup, it is very useful to compare the log files of the...